Acoustical waves may be generated by a transducer that converts modulated electrical signals into compression waves in air. This is commonly done by an electromagnetic system that drives an air piston commonly called a speaker cone. The electromagnetic portion consists of a voice coil which is placed in the field of permanent magnetic pole pieces. The coil is rigidly attached to a conically shaped diaphram which moves in accordance with the current in the coil; this conical diaphram acts as an air piston and is commonly known as a speaker cone. The volume of the air displaced in every excursion of the air piston determines the loudness of the sound; the time rate of excursions determine the frequency. Ordinarily, a high-power audio speaker obtains loudness by having physically large air pistons. In this invention, a single large air displacement is caused by each excursion of the coil because the inventor has mechanically and pneumatically coupled together two air pistons of approximately equal area. The two air pistons are back to back and operated from a common coil and permanent magnet and the pistons are mechanically coupled by a rigid link and pneumatically coupled by an interconnecting orifice.